Shank stiffener for shoe soles



Sept. 25, 1923. 1,468,856

A. T. BALCH SHANK STIFFENER FOR SHOE SOLES Filed June 25, 1923 PatentedSept. 25, 1923.

ALFRED T. BALCH, F BROCKTON, MASSACHUSETTS, ASSIGNOR TO H. F. CRAWFORDMANUFACTURING COMPANY, 0F BROCKTON, MASSACHUSETTS, A CORPORATION 0FMASSACHUSETTS.

SHANK STIFFENER FOR SHOE SOLES.

Application led .Tune 23, 1923. Serial No. 647,301.

To aZ 1li/0m it may concern Be it known that I, ALFRED T. BALGH, acitizen of the United States, residing at Brockton, in the county ofPlymouth and 5 State of Massachusetts, have invented new and usefulImprovements in Shank Stiff'- eners for Shoe Soles, of which thefollowing a specification.

This application is a continuation in part of my application filedJanuary 2, 1923,

Serial No. 610,149.

The invention is embodied in a. resilient shank stiffener, adapted to beinterposed betweenthe shank portions of the insole and outsole ot' ashoe,`said stitfener having 5 mentioned raised central portion of thestiffener. Une of the members is slotted to cooperate with one ormore ofthe rivets in permitting a limited sliding movementJ of the slottedmember on the other mem ber, and adownward yielding of the saidcentrally raisedportion of the stifiener.

The desired resilience is provided by making one of said members oftempered steel, adapted to assume a predetermined normal form whenreleased from flexing pressure, and the other of relatively soft steel.The members may have the same normal curvature, so that they contactwith each other from end to end, or the inner member may be bowed, sothat it contacts with the outer member only at its end portions, and isspaced at its central portion from the outer member, the centrallyraised portion of the stiffener formed b v the inner member, being,therefore, depressible independently of the portion formed by the outermember.

Other features of construction will be described hereinafter.

Of the accompanying drawings forming a part of this specification,

Figure l is a bottom plan View of a portion of a shoe having a shankstiffener embodying the invention, before the application of theoutsole.

Figure 2 is a section on line 2-2 of Figure l, the outsole being shownby dotted lines. I

Figure 3 is a perspective view of the stiffener.

Figure 4 is a plan view showing a modification.

Figure 5 is a section on line 5*-5 of Figure 4.

Figure 6 is a plan view showing another modification.

Figure 7 is a section on line 7-7 of Figure 6.

The same reference characters indicate the saine' parts in all of thefigures.

I will first describe' the invention as shown by Figures 1, 2, 3, 4 and5.

My improved stiffener is adapted for use with a shoe, the insole a ofwhich has a securing member, such as a bifurcated rivet Z), inserted inthe insole, as shown by Figure 2, the head the rivet being flush withthe upper surface of the insole, and the bifurcations of its shank beingbent below the lower surface to form ears e, c which project in oppositedirections and are slightly spaced from the under surface of the innersole, as shown by the Crawford Patent No. 1,029,278, umd June 11, 1912.

The stiffener comprises an outer'niember 12, which is a thin steelstrip. having in its forward end a slot 13, adapted to receive the shankof the rivet 7), the arrangement oeing such that the forward end of themember 12 is adapted to slide between the ears c and the bottom surface.of the insole, as described in the Crawford patent. The opposite endportion of the member 12 may he provided with an orifice 14, adapted toreceive a tack 15, driven into the insole, as shown by Figure 2,

The member 12 is curved, to conform to the normal curvature of the shankportion of an outsole d. v

The stiffener also comprises an inner member 1G. which is also a thinstrip of steel` and has a more abrupt curvature than the outer member12` the end portionl of' the inner member bearing on corresponding portions of the outer member. The inner member is spaced between its endportions trom the outer member, as shown by Figure 2.

The members 12 and 16 are inseparably connected by connections betweentheir end portions, permitting independent tlexure ot each member, sothat the outer member is adapted to conform independently to ilexuresot' the shank portion of the outsole, and the inner member constitutesan independently flexible yielding support for the shank portion oi' theinsole.

Said connections are preferably embodied in headed rivets 17, fixed toone ot the members, and passing through the end portions of the othermember, the last-mentioned member being slotted to permit independentFlexure ot each member.

1n this instance 1 show the rivets 17 fixed to the outer member 12, andpassing through Slots 18 in the inner member, each rivet having a headat one end bearing on one ot the members, and an upset end forminganother head bearing on the other member.

Then the shoe is flexed, as in the act ot walking, the outer member isadapted to conform to the tlexure, its slotted end sliding in contactwith the securing member I), and its ears c. The inner member 16 may beflexed with the outer member` and is independently flexible and adaptedto be pressed at its central portion toward the outer member by theweight ot the wearer, the slots 18, and the rivets 17, permittingr thedescribed tiexures ot each of said members.

It will be seen that the inner member 16 constitutes an arch support,which conforms to changes otl 'form of the arch ot a human foot, thecurvature of the inner member being reduced by an increase ot' pressurethereon, and restored to normal when the pressure is removed.

Figures et and 5 show one slot 18 instead of two, this being formed inthe rear end portion of the inner member 16. In other respects thestitliener may be the same 21S that shown by Figures 1, 2 and 3.

The embodiment ot' the invention shown by Figures G and 7 includes aninner member 20, and an outer member 21, connected by rivets 22. Thesaid members have the same curvature, so that they contact with eachother from end to end, instead otl being messes spaced apart at theircentral portions. A single slot 23 is provided, this being formed in theouter member 21.

1n each embodiment of the invention the resilience ot the stifeneradapting it to be flexed from its normal curvature and to returnthereto, is provided by making one ot the members of tempered steel andthe other of relatively soft steel. rThe tempered member, which may bethe member 16 shown by Figures 1 to 5, and the member 21 shown byFigures 6 and 7, may be shorter, and is preferably somewhat thicker thanthe other member .12er 20. The tempered member and the rivets maintainthe sotter member at a suitable curvature. The cost ot manufacture isthus materially reduced, and the expense involvedin tempering one of themembers eliminated, the decreased length of the tempered membereffecting a. saving of material.

ln assembling the members 1 space the ends of the shorter member fromthe ends of the longer member, so that the latter presents two endextensions ot single thickness at the opposite ends of the stitl'ener,one of these extensions containing the slot 18, and the other theorilice 14. The devices which secure the stitlener to the inner sole,`therefore, engage only the said extensions.

1 claim:

A resilient shank stitliener adapted to be interposed between an outerand an inner sole and con'iprising an outer and au inner metal member,and rivets inseparably connecting the same, said members being curved sothat the under side of the stifener has a centrally raised portion whichconforms to the curvature ot the shank portion of a last'bottom, one ofsaid members being slotted to permit a limited sliding movement thereofon the other member. and a downward yielding ot the centrally raisedportion, one ot said members being ot steel, tempered to impart suitableresilience to the stitllener` and the other ot relatively sott. steel,maintained at the desired curvature by the tempered member and the saidrivets.

ln testimony whereof 1 have attixed my signature.

ALFRED T. BALCH.

